Most cars today use transmissions that provide three or four specific speed ratios. A continuously variable speed transmission can make the car run more efficiently, saving fuel costs. Thus, in some instances continuously variable speed transmissions have been used which incorporate variable speed belt drives and toroidal continuously variable speed transmissions. However, problems remain with such designs.
In a typical belt driven continuously variable speed transmission much efficiency is lost due to slippage. In such systems where friction is used to transmit power, rubber v-belts may slip resulting in losses. What is needed is a design for a continuously variable speed transmission which avoids the loss of efficiency due to slippage associated with conventional variable speed transmission designs.